Neural oscillation is rhythmic or repetitive neural activity in the
central nervous system.
Neural tissue can generate
oscillatory activity in many ways, driven either by mechanisms within individual
neurons or by interactions between neurons. In individual neurons, oscillations can appear either as oscillations in
membrane potential or as rhythmic patterns of
action potentials, which then produce oscillatory activation of
post-synaptic neurons. At the level of
neural ensembles, synchronized activity of large numbers of neurons can give rise to
macroscopic oscillations, which can be observed in the
electroencephalogram (EEG). Oscillatory activity in groups of neurons generally arises from feedback connections between the neurons that result in the synchronization of their firing patterns. The interaction between neurons can give rise to oscillations at a different frequency than the firing frequency of individual neurons. A well-known example of macroscopic neural oscillations is
alpha activity.